PARASITOLOGY. 41 
whose quarters are separated only by a partition, 
may get upon horses and cattle and cause temporary 
parasitism. Each parasite has its own host or hosts 
and will not live permanently upon another. 
Lice oF Brrps. 
The Large Hen Louse—MeENopoN BISERIATUM. 
This is the largest louse found upon the hen. It 
is about one-twelfth of an inch in length, light in 
color, with mouth parts arranged for mastication as 
illustrated in Fig. 10. The free extremities of the legs 
are provided with hooklets which aid in holding on. 
The smaller variety of this genus, MENoPON 
PaLLipuM, also has been studied, but is far less 
common in the United States. This louse is found on 
young and old chickens. 
Fig. 10.—Menopon biseriatum (from a hen), greatly enlarged; a, 
head, which is provided with mouth parts; b, thorax provided with 
three pairs of legs; c, abdomen. 
The Turkey Louse—Goniopes Stytirer. This 
louse is found on turkeys and is thicker than the 
one just described. Like it, the mouth parts are 
arranged for mastication. It is illustrated in Fig. 11. 
Lipeurus JnFuscaTus. This is another louse that 
may infest chickens. A study of Fig. 13, shows its 
mouth parts and legs similar to the other lice. Its 
general shape is different. It is not so common as the 
large hen louse. 
